Mute structure for musical instruments



Nov. 13, 1951 w. w. RUDD 2,574,591

MUTE STRUCTURE FOR MUSICAL INSTRUMENTS Filed Oct. 5, 1948 IN VEN TOR.

William W Budd BY M, y

patented Nov. 13, 1951 UNITED STATES F iTENT OFFICE MUTE STRUCTURE FOR MUSICAL INSTRUMENTS 14 Claims.

1 This invention relates to musical instruments of the air-column type, more particularly to mute structure adapted to be placed in the bell of an air-column instrument for producing novel musical effects and the invention has for an object the provision for improved structures of this character.

Although the invention is applicable generally to musical instruments of the air-column type having a bell, it is particularly useful, and is disclosed herein, in connection with brass instruments of the type commonly known as trumpets. Heretofore it has been the practice in the brass sections of many orchestras to employ a so-called cup mute on certain of the instruments, the trumpets, for example, in the rendition of various compositions. Because of the large reduction in the volume of sound which can be produced while employing cup mutes, it has been necessary to position the muted instrument closely adjacent the microphone of the conventional loudspeaker or public address system which is usually employed in auditoriums, ballrooms and the like. Even when so employed in conjunction with a microphone closely adjacent to the instrument, many of the resonant tones and auditorium in which the orchestra may be playing.

In carrying out the invention in one form, mute structure for an air-column musical instrument of the type having a bell is provided, comprising a mute member insertible into the bell and a cup member supported on the extending mute -member and facing the open end of the bell in closely spaced relation thereto, together with sound pick-up means carried by the mute member within the cup member and adapted to be electrically connected in an amplifier and loudspeaker circuit, more particularly the pick-up means or microphone is mounted within a chamber formed in the mute member and having access to the interior of the cup member, the

microphone being imbedded in and wholly supported by a body of porous, resilient, spongy "material as, for example, sponge rubber. For a more complete understanding of the invention, reference should now be had to the drawing in which:

Fig. 1 is a somewhat diagrammatic view of an air-column instrument or trumpet provided with mute structure embodying the present invention,

2 the mute structure being connected to a suitable amplifier and loud-speaker;

Fig. 2 is an elevation view on a large scale of the mute structure shown in Fig. l, the bell end of the trumpet being shown in phantom by means of broken lines;

Fig. 3 is a front end view of the mute structure of Fig. 2; and

Fig. 4 is an elevational view, similar to Fig. 2, of the mute structure but being partially in section in order to illustrate the internal structure thereof.

Referring now to the drawing, invention is shown as embodied in an electrified mute structure 10 adapted to be supported in the bell of a trumpet I l and electrically connected by means of suitable conductors 12 with a conventional amplifier and loud-speaker [3. As shown in Figs. 2 and i, the mute structure comprises a hollow tapered mute-member 14 which is preferably formed of thin maple wood on the order of of an inch in thickness, the tapered member l4 being open at its smaller end and terminating at its larger end in cylindrical portion 15, preferably formed integrally therewith. Mounted on the cylindrical portion [5 of the mute-member 14, preferably by a slip fit, is a cup member I6 which is likewise formed of thin maple wood of the thickness on the order of of an inch. Supported within the hollow member l4 immediately adjacent the juncture of the cylindrical portion IS with the tapered portion of the member is a disc 11, preferably formed of thin metallic material such as, for example, Phosphor bronze, the disc I! being glued or otherwise secured to a wooden supporting ring I 8. Suitably secured within the hollow mutemember I adjacent the opposite end of the cylindrical portion [5 is a closure disc [9 preferably glued in place and likewise formed of thin maple wood. If desired, a decorative grilled member 20, suitably secured to the outer surface of the closuredisc 19, may be provided.

As will be apparent from Fig. 4, the metallic disc I! and the wooden closure disc l9 serve to define a chamber 2i within the cylindrical portion l5 of the mute-member and a plurality of apertures 22 are provided in the peripheral wall of this chamber for establishing communication between the chamber 2| and the interior of the cup member l6. Disposed within the chamber 2| and substantially filling the same is a body of porous resilient spongy material 23, such for example as sponge rubber, and a suitable microphone or pick-up device 24, is embedded in the spongy rubber pad 23 and entirely supported therein so as to be free of mechanical connection with the walls of the chamber 2|. Although any desired arrangement may be employed for mounting the microphone 24 in the body 23, it

has been found satisfactory merely to slit the body 23 on one side and then to force the microphone into the pocket thus formed within the body. As shown in Fig. 4, the microphone 2Q is connected by suitable conductors 25 which extend outwardly of the body 23 and through one of the apertures 22 to a pair of microphone jacks 26 (only one of which is shown), carried by the cup member It. A suitable double pronged plug 21 (Fig. 1) may be employed, which is insertable in the jacks 26 and serves to connect the conductors l2 leading from the amplifier and loud-speaker to the microphone 24 by way of the jacks 26 and the-conductors 25.

In order to mount the mute structure on the trumpet H with the tapered mute-member 14, positioned in the bell of the trumpet, a plurality of clips or spring fingers 29 are provided, secured to the cup member l6 and suitably spaced about the periphery thereof, which clips are adapted to engage the flared end of the trumpet bell as shown best in Fig. 2 so as to support the mute structure on the trumpet with the open end of the cup 16 spaced slightly from the open end of the bell, the outer periphery of the cup member 16 being of slightly less diameter than the outer periphery of the bell. Preferably the clips 29 are formed of rubber covered piano wire so as to prevent metal-to-metal contact with the trumpet bell. Likewise, in order to properly position the mute structure, a number of sponge rubber pads 30 are provided, suitably secured on the tapered portion M of the mute structure for engaging 'the inner surface of the trumpet bell, as shown best in Fig. 2.

With the mute structure positioned on the trumpet as shown and described, it will be apparentthat sound waves entering the open inner end of the tapered portion M will impinge on the metal disc I! and be trapped within the hollow tapered portion l4. At the same time sound. waves passing around the surface of the tapered portion I4 will enter the interior of the cup 16 and may pass into the chamber 21 through the vent holes or apertures 22. Whether or not the sound waves reaching the pick-up device or microphone 24 enter the chamber 2i entirely through the apertures 22 or whether the diaphragm l1 operates as a sound transmitting vibrating member is not entirely understood, but it has been found in practice, that with mute structures arranged as shown on the trumpet bell and connected in a suitable amplifier and loudspeaker circuit, pleasing and novel musical effects maybe produced characterized by pronounced overtones and resonant effects.

While a particular embodiment of the invention has been shown, it will be understood, of

course, that the invention .is not to be limited thereto since many modifications may be made and it is contemplated therefore by the patented claims to cover any such modifications as fall within the true spirit and scope of the invention.

What is desired to be secured by Letters Patent of the United States is:

1. Mute structure for an air-column musical instrument of the type having a bell, comprising a mute-member insertable into said bell, a cup member supported on the extending end of said mute-member and facing the open end 0f said bell in closely spaced relation thereto,

:sound pick-up means carried by said mute-member within said cup member, and means for elec= 'trically connecting said pick-up means in an amplifier and loud-speaker circuit.

2. Mute structure for an air-column musical instrument of the type having a bell, comprising a mute-member insertable into said bell, a cup member supported on the extending end of said mute-member and facing the open end of said bell in closely spaced relation thereto, a body of porous resilient spongy material carried by said mute-member within said cup member, sound pick-up means supported solely by said body, and means for electrically connecting said pick-up means in an amplifier and loud-speaker circuit.

3. Mute structure for an air-column musical instrument of the type having a bell, comprising a mute-member insertable into said bell, a cup member supported oh the extending end of said mute-member and facing the open end of said bell in closely spaced relation thereto, a body of porous resilient spongy material carried by said mute-member within said cu member, sound pick-up means embedded in said body, and means for electrically connecting said pick-up "means in an amplifier and loud-speaker circuit.

4. Mute structure for an air-column musical instrument of the type having a bell, comprising a mute-member insertable into said bell, a cu member supported on the extending end of said mute-member and facing the open end of said bell in closely spaced relation thereto, a body of porous resilient spongy material carried by said mute-member within said cup member, soundpick-up means completely embedded in and supported solely by said body, and means for electrically connecting said pick-up means in an amplifier and loud-speaker circuit.

5. Mute structure for an air-column musical instrument of the type having a bell, comprising a tapered mute-member, means for supporting said mute-member in said bellin spaced relation thereto, a cup member supported on the extending end of said mute-member and facing the open end of said bell in closely spaced relation thereto, sound pick-up means carried'by said mute-member within said cup member, and means for electrically connecting said pi'ckup means in an amplifier and loud-speaker circuit.

6. Mute structure for an air-column musical instrument of the type having a bell, comprising a tapered mute+member,-means for supporting said mute-member in said bell in spaced relation thereto, a cup member supported on the extending end of said mute-member and, facing the open end of said bell in closely spaced relation thereto, a body of porous resilient spongy material carried by said extending end of said mute-member within said cup member, sound pick-up means supported solely by said body, and means for electrically connecting said pick-up means in an amplifier and loud-speaker circuit.

7. Mute structure for an air-column musical instrument of the type having a bell, comprisin a tapered mute-member, means for supporting said mute-member in said bell in-spaced relation thereto, a cup member supported on the extending end of said mute-member and facing the open end of said bell in closely spaced relation thereto, a body of porous resilent spongy material carried by said extending end of said mute-member within said cup member, sound pick-up means embedded in said body substantially centrally thereof and supported solely thereby, and means for electrically connecting said pick-up means in an amplifier and loudspeaker circuit.

8. Mute structure for an air-column musical instrument of the type having a bell, comprising a hollow, thin walled tapered mute-member insertable into said bell and open at its apex end, partition means extending across said hollow member in spaced relation to said apex end and defining a chamber adjacent the extending end of said mute-member closed with respect to said apex end, a cup member supported on said extending end or said mute-member facing the open end of said bell and surrounding said chamber, said chamber having apertures in a wall thereof acoustically communicating said chamber with the interior of said cup member, and amplifying and sound reproducing means including sound pick-up means disposed in said chamber.

9. Mute structure for an air-column musical instrument of the type having a bell, comprising a hollow, thin walled, tapered mute-member insertable into said bell and open at its apex end, partition means extending across said hollow member in spaced relation to said apex end and defining a chamber adjacent the extending end of said mute-member closed with respect to said apex end, a cup member supported on said extending end of said mute-member facing the open end of said bell and surrounding said chamber, said chamber having apertures in a wall thereof acoustically communicating said chamber with the interior of said cup member, a body of porous, resilient, spongy material in said chamber, and amplifying and sound reproducing means including a microphone in said chamber supported solely by said body.

10. Mute structure for an air-column musical instrument of the type having a bell, comprising a hollow, thin walled tapered mute-member insertable into said bell and open at its apex end, partition means extending across said hollow member in spaced relation to said apex end and defining a chamber adjacent the extending end of said mute-member closed with respect to said apex end, a cup member supported on said extendin end of said mute-member facing the open end of said bell and surrounding said chamber, said chamber having apertures in a wall thereof acoustically communicating said chamber with the interior of said cup member, a body of porous, resilient, spongy material substantially filling said chamber, and amplifying and sound reproducing means including a microphone embedded in said body substantially centrally of said chamber.

11. Mute structure for an air-column musical instrument of the type having a bell, comprising a hollow, thin walled tapered mute-member insertable into said bell and open at its apex end, partition means extending across said hollow member in spaced relation to said apex end and defining a chamber adjacent the extending end of said mute-member closed with respect to said apex end, a cup member supported on said extending end of said mute-member facing the open end of said bell and surrounding said chamber, said chamber having apertures in a wall thereof acoustically communicating said chamber with the interior of said cup member, a body of porous, resilient, spongy material substantially filling said chamber, a microphone embedded in said body and supported solely thereby within said chamber, and means for electrically connecting said microphone in an amplifying and sound reproducing circuit.

12. Mute structure for an air-column musical instrument of the type having a bell, comprising a hollow tapered mute-member having thin walls formed of wood, means for supporting said mute-member in said bell in spaced relation thereto, said mute-member being open at its apex end, partition means comprising a thin metallic disc extending across said mute-member in spaced relation to said apex end and defining one wall of a chamber in the extending end of said mute-member closed with respect to said apex end, a cup member comprising a thin wooden wall supported on said extending end of said mute-member facing the open end of said bell and surrounding said chamber, said chamber acoustically communicating with the interior of said cup member, and sound amplifying and reproducing means including sound pick-up means disposed in said chamber.

13. Mute structure for an air-column musical instrument of the type having a bell, comprising a hollow tapered mute-member having thin walls formed of wood, means for supporting said mute-member in said bell in spaced relation thereto, said mute-member being open at its apex end, partition means comprising a thin metallic disc extending across said mute-member in spaced relation to said apex end and defining one wall of a chamber in the extending end of said mute-member closed with respect to said apex end, a cup member comprising a thin wooden wall supported on said extending end of said mute-member facing the open end of said bell and surrounding said chamber, said chamber acoustically communicating with the interior of said cup member, a body of porous, resilient, spongy material substantially filling said chamber, and amplifying and sound reproducing means including a microphone embedded in said body substantially centrally of said chamber.

14. Mute structure for an air-column musical instrument of the type having a bell, comprising a hollow tapered mute-member having thin walls formed of wood, means for supporting said mute-member in said bell in spaced relation thereto, said mute-member being open at its apex end, partition means comprising a thin metallic disc extending across said mute-member in spaced relation to said apex end and defining one wall of a chamber in the extending end of said mute-member closed with respect to said apex end, a cup member comprising a thin woden wall supported on said extending end of said mute-member facing the open end of said bell and surrounding said chamber, said chamber acoustically communicating with the interior of said cup member, a body of porous, resilient, spongy material substantially filling said chamber, a microphone embedded in said body and supported solely thereby within said chamber, and means for electrically connecting said microphone in an amplifying and sound reproducing circuit.

WILLIAM W. RUDD.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,138,500 Miessner Nov. 29, 1938 2,252,847 Greenspan Aug. 19, 1941 2,460,408 Babicky Feb. 1, 1949 

